An electronic mail (“e-mail”) message may comprise one or more of the following: a message header, a message body, optionally one or more encoded attachments, one or more encrypted session keys (e.g. if the message is encrypted), and digital signature and signature-related information. The message header may comprise the following header fields, for example: “To”, “From”, “Cc”, “Bcc”, “Date”, “Reply-To”, and “Subject”.
Electronic mail messages may be generally encoded using one of a number of known protocols to facilitate secure message communication. Examples of known standards and protocols for facilitating secure message communication include the Secure Multiple Internet Mail Extensions (“S/MIME”) protocol and the Pretty Good Privacy™ (PGP) protocol.